Obesity is a growing global concern, as the number of individuals classified as overweight, obese, or morbidly obese continues to increase every year. Obesity is associated with several co-morbidities, including hypertension, type II diabetes, and sleep apnea. Morbid obesity, defined as when a person is 100 pounds or more over ideal body weight or having a body mass index (BMI) of 40 or greater, poses the greatest risks for severe health problems. Accordingly, a great deal of attention is being focused on treating patients with this condition. One method of treating morbid obesity is the placement of a restriction device, such as an elongated band, around the upper portion of the stomach. Gastric bands are typically comprised of a fluid-filled elastomeric balloon with fixed endpoints that encircles the stomach just inferior to the esophageal-gastric junction. This forms a small gastric pouch above the band and a reduced stoma opening inferior to the gastro-esophageal junction in the stomach. When fluid is infused into the balloon, the band expands against the stomach creating further food intake restriction or a smaller stoma opening in the stomach. To decrease this restriction level, fluid is removed from the band. The effect of the band is to reduce the available stomach volume and thus the amount of food that can be consumed before becoming “full.”
Food restriction devices have also comprised mechanically adjusted bands that similarly encircle the upper portion of the stomach. These bands include any number of resilient materials or gearing devices, as well as drive members, for adjusting the bands. Additionally, gastric bands have been developed that include both hydraulic and mechanical drive elements. An example of such an adjustable gastric band is disclosed in U.S. Pat. No. 6,067,991, entitled “Mechanical Food Intake Restriction Device” which issued on May 30, 2000, and is incorporated herein by reference. Another method for limiting the available food volume in the stomach cavity is implanting an inflatable elastomeric balloon within the stomach cavity itself. The balloon is filled with a fluid to expand against the stomach walls and, thereby, decrease the available food volume within the stomach.
With each of the above-described food limitation devices, safe, effective treatment requires that the device be regularly monitored and adjusted to vary the degree of affect on food intake. With banding devices, the gastric pouch above the band may substantially increase in size following the initial implantation. Accordingly, the stoma opening in the stomach must initially be made large enough to enable the patient to receive adequate nutrition while the stomach adapts to the banding device. As the patient's body adapts to the implant, the band may be adjusted to vary the stoma size. In addition, it is desirable to vary the stoma size in order to accommodate changes in the patient's body or treatment regime, or in a more urgent case, to relieve an obstruction or severe esophageal dysmotility or dilatation. Traditionally, adjusting a hydraulic gastric band required a scheduled clinician visit during which a Huber (non-coring) hypodermic needle and syringe were used to penetrate the patient's skin and add or remove fluid from the balloon. More recently, devices have been developed which enable non-invasive adjustments of the band. An external programmer communicates with the implant using telemetry to control the stoma diameter of the band. During a scheduled visit, a physician places a hand-held portion of the programmer near the implant and transmits power and command signals to the implant. The implant in turn adjusts the stoma diameter of the band and transmits a response command to the programmer.
During these gastric band adjustments, it has been difficult to determine how the adjustment is proceeding, and whether an adjustment will have its intended effect. In an attempt to determine the efficacy of an adjustment, some physicians have used fluoroscopy with a Barium swallow as the adjustment is being performed. However, fluoroscopy is both expensive and undesirable due to the radiation doses incurred by both the physician and patient. Other physicians have instructed the patient to drink a glass of water during or after the adjustment to determine whether the water can pass through the adjusted stoma. This method, however, only assures that the patient is not obstructed at that time, and does not provide any information about the efficacy of the adjustment or the impact of the adjustment the following day as the patient begins to consume more solid foods. Oftentimes, physicians may simply adopt an experimental method based upon their prior experience, and the results of an adjustment may not be discovered until hours or days later, when the patient experiences a complete obstruction of the stomach cavity.
Another problem that can arise is the ability to handle a port, such as a fluid port, used to fluidically communicate with the gastric band to increase or decrease the restriction the band provides. For example, in order to introduce additional fluid to increase the restriction of the gastric band, a Huber needle must be inserted through the skin and into the port septum. This can be difficult as the stomach anatomy is not a flat surface and the port may be angled, the port may shift locations beneath the skin, or the port can flip over entirely.
Accordingly, there remains a need for improved methods and devices for reorienting a port implanted under the skin.